I believe that the fortune-telling is not correct, especially the blood type fortune-telling. “What is your blood type?” We sometimes ask our new friends this question. It is a character diagnosis and the blood type fortune-telling is often used at drinking session by Japanese. We judge people based on their blood type. Generally, type of A blood is punctilious, type of B is self-centered, type of O is magnanimous and type of AB, but it is groundless to change the personality by type of blood. Why do people believe it? This time, I focus on the difference with other country, evaluation from another person and psychological factor.
In the first place, this is custom peculiar to Japanese. There is much O-type in the American continent particularly there is an area where is seen in the ratio of O-type over 80% in South America. In India and the Near and Middle East, there is many B-type and there is many A-type in Asia, Europe and Canada. In other countries, it is often same type of blood when people make new friends. They need not ask their friends about type of blood, there are very many people who do not know own blood type, and there is usually no custom that people judge the character of the partner from a blood type. The ratio of Japanese blood types are about A 40%, B 20%, O 30%, AB 10%. Japanese are all types of blood. The case is very rare in the world.
In the second place, we always worry about how other people are viewing us. In the case of A-type, if we are said, “You are cautious” we feel relieved because we think the character is A-type. We do autosuggestion unconsciously and we become to behave ourselves like A-type. It becomes mean to recognize as one person.
Lastly, people are influenced by “Barnum effect”. We think explanation about the character that it is vague and it is common corresponding to anyone. When people felt partner’s character we had seen some actions, heard some news, or talked. The characters we felt are based on the time and location but we pay attention to only the character. A few years ago, the book of the blood type diagnosis such as “The textbook of the type AB” has become the bestseller before, but it will become reputation even if I make contents the same really and changed only a cover into “The textbook of the O-type”.
The blood type fortune-telling is autosuggestion peculiar to Japanese but actually it is not correct. However, we can use it in conversation as a topic. It becomes mean that we make friends close friends. I want to make friends of AB-type because they are interesting, little strange, and rare not only in Japan but also in the world, and I am type of AB blood.